Effect of chloroquine on intracellular radioiron distribution. Cells were labeled with 59Fe-labeled human diferric transferrin during the first 6 days of phase II (EPO-dependent phase, see Materials and Methods), then washed, and reincubated in fresh nonradioactive medium containing different concentrations of chloroquine. On day 9 of phase II, cells were harvested and lysed. (A) Results obtained by ferritin immunoprecipitation and heme extraction of three individual experiments obtained from cultures of three different normal donors. (B) Cell lysates were separated by SDS-PAGE followed by phosphor-imaging. Human placental ferritin and Hb were used as standards (not shown). Lane 1, 6 days in phase II, before treatment. Lanes 2 to 5, 9 days in phase II, chloroquine at 0, 5, 10, and 15 μmol/L, respectively.
